The present invention relates to a method and apparatus for mounting a pre-cast panel, such as a pre-cast concrete or brick facade, to a structure, such as a building. More particularly, the invention relates to mounting such panels in a manner that facilitates positioning the panel on the structure.
A problem in mounting pre-cast panels such as concrete or brick facades to buildings is that the panels are very heavy, and are therefore difficult to position accurately for proper alignment to the building. This is especially the case in high-rise buildings where the panels must be hoisted to great heights.
According to a preferred prior art scheme for mounting such panels, the panels are provided with a recess or pocket extending into a side thereof and having a ceiling surface adapted to rest on the head of a vertically oriented bolt threadably received in a steel member attached to a side of the building to which the panel is to be mounted. With the panel roughly in position, threading the bolt in one direction or the other raises or lowers the panel to position the panel vertically.
A problem remaining, however, is that there is no provision to facilitate precise adjustment of the position of the panel inwardly toward the building and outwardly away from the building. Von Wedel, U.S. Pat. No. 3,465,996 proposes a xe2x80x9cuniversal connecting arrangementxe2x80x9d that provides for adjusting of face or cover plates on building walls inwardly and outwardly. An angle bracket and a Z-shaped bracket are welded to one another and secured to the wall of the structure. The brackets define a longitudinally extending glide way on which rests an intermediate member of box-shaped cross-section. The intermediate member is provided on its upper most face with a longitudinally extending slot which is inclined away from the wall. A screw extending from a bracket attached to the face plate extends into this slot so that movement of the intermediate member slides the screw in this slot and thereby moves the face plate toward or away from the wall. Turning the screw moves the face plate vertically.
An important drawback of this approach is that adjustment inwardly and outwardly is not independent of horizontal positioning of the panel, so that the former affects the latter and accurate positioning is therefore made more complex and time consuming.
Another drawback of the approach is that the angle bracket and Z-shaped bracket will physically interfere with the face or cover plate without some specialized adaptation of the face or cover plate. This is important because the angle bracket and Z-shaped bracket are intended to continue supporting the weight of the face or cover plate once it is finally positioned, so that these components must be over-sized accordingly. A sizable relief will therefore be required in the face or cover plate and if it is desired to minimize the thickness of the face or cover plate, this may not be accommodable.
Chambers, U.S. Pat. No. 3,715,850 proposes an xe2x80x9cadjustable mounting devicexe2x80x9d including a tubular base insert that can be attached to either a structural steel or reinforced concrete framework and which is in the form of a hollow internally threaded tubular member. An adjustable table plate is connected to the hollow tubular member. The table plate comprises a disc member of circular outer configuration wherein a threaded cantilever stem extends from an inner face thereof. The table plate is provided with a plurality of apertures positioned radially from the central axis thereof. An L shaped bracket has a base flange and a pair of spaced apart attachment flange plates extending perpendicularly in parallel planes. A plurality of horizontally extending aperture pairs are provided in the attachment flange plates and a pair of elongated slots are provided in the base flange. The angle bracket is connected to the table plate by a nut and bolt member passing through one of the elongated slots and the aperture of the respective aperture pairs. By selecting a particular aperture pair or by using any of the apertures in the table plate, the vertical height of the bracket plate is adjustable by eccentric increments of adjustment. The table plate is adjustable inwardly and outwardly by rotating the table plate, threading the cantilever stem inwardly and outwardly through the hollow tubular sleeve.
This approach is not adapted for mounting pre-cast panels to structures. Particularly, the nut and bolt members passing through the elongated slots must support the weight of the panel by frictional force (i.e., tightening of a laterally oriented bolt extending through apertures in the table plate and base flange), making the approach impractical for heavy panels. Another problem with the approach is that vertical adjustment by slots and the alignment of a table plate with pairs of apertures requires more complex hardware and more manual operations than the prior art bolt and pocket. Yet another drawback of the approach is that it provides only discrete increments of adjustment rather than the precise, infinitely variable control provided by the bolt and pocket.
Accordingly, there is a need for a novel and improved method and apparatus for mounting a pre-cast panel to a structure that provides for maintaining the ease, economy and precision of adjustment provided by the prior art bolt and pocket, that provides in addition for adjusting the position of the panel inwardly and outwardly without the disadvantages of the prior art.
The method and apparatus for mounting a pre-cast panel to a structure of the present invention solves the aforementioned problems and meets the aforementioned needs by providing a pocket in the pre-cast panel extending into a side thereof and having a ceiling surface adapted to rest on a height-adjustable member such as the head of a bolt threadably received in an extendable member attached to a side of the structure to which the panel is to be mounted. The extendable member is carried by a base member mounted to the structure, the base member supporting the extendable member so that the extendable member is enabled to extend along an axis and move inwardly and outwardly relative to the base portion along the axis. Preferably, the extendable member is further constrained by the base member so that the extendable member is not permitted to rotate substantially about the axis.
Typically, for use with structures having vertical walls, the extendable member is oriented along a horizontal axis and the bolt is oriented vertically. Then, with the panel roughly in position, threading the bolt in one direction or the other raises or lowers the panel, to position the panel vertically, and the extending member is adjusted with respect to the base member to position the panel inwardly and outwardly.
Therefore, it is a principal object of the present invention to provide a novel and improved method and apparatus for mounting a pre-cast panel to a structure.
It is a further object of the present invention to provide a method and apparatus for mounting a pre-cast panel to a structure that provides for ease of adjustment of the position of the panel to the structure.
It is still a further object of the present invention to provide such a method and apparatus for mounting a pre-cast panel to a structure that provides for precision of the adjustment.
It is yet a further object of the present invention to provide such a method and apparatus for mounting a pre-cast panel to a structure that provides for economy of manufacture and use.
It is another object of the present invention to provide such a method and apparatus for mounting a pre-cast panel to a structure that provides for minimizing the relief space required in the panel.
It is still another object of the present invention to provide such a method and apparatus for mounting a pre-cast panel to a structure that provides for minimizing the complexity of the components required, especially with respect to panels that are heavy.
The foregoing and other objects, features and advantages of the present invention will be more readily understood upon consideration of the following detailed description of the invention, taken in conjunction with the following drawings.